i2c communication not working in ncs but working on nrf5 sdk

[Gaurav]

I have tried all the configs on device tree to make the sensor work reliably, but it fails. Like I have LSM6DSOX as IMU and it works for sometime and then On power on reset , device starts to show as not ready 

device_is_ready(lsm_i2c.bus) this fails.

Providing config files and schematic of the SDA and SCL line-

&i2c0 {
    lsm6dsox: lsm6dsox@6A {
		compatible = "st,lsm6dso";
		reg = <0x6A>;
    };
	stc3117: stc3117@70 {
		compatible = "i2c-device";
		reg = <0x70>;
	};
	mlx60732: mlx60732@3A {
		compatible = "i2c-device";
		reg = <0x3A>;
	};
};

&i2c1 {
	status = "okay";
	maxm86161: maxm86161@62 {
		compatible = "i2c-device";
		reg = <0x62>;
	};
};

And this is pin ctrl config for the same -

/*
 * Copyright (c) 2022 Nordic Semiconductor
 * SPDX-License-Identifier: Apache-2.0
 */

&pinctrl {
	uart0_default: uart0_default {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 6)>,
				<NRF_PSEL(UART_RTS, 0, 5)>;
		};
		group2 {
			psels = <NRF_PSEL(UART_RX, 0, 8)>,
				<NRF_PSEL(UART_CTS, 0, 7)>;
			bias-pull-up;
		};
	};

	uart0_sleep: uart0_sleep {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 6)>,
				<NRF_PSEL(UART_RX, 0, 8)>,
				<NRF_PSEL(UART_RTS, 0, 5)>,
				<NRF_PSEL(UART_CTS, 0, 7)>;
			low-power-enable;
		};
	};

	uart1_default: uart1_default {
		group1 {
			psels = <NRF_PSEL(UART_RX, 1, 1)>;
			bias-pull-up;
		};
		group2 {
			psels = <NRF_PSEL(UART_TX, 1, 2)>;
		};
	};

	uart1_sleep: uart1_sleep {
		group1 {
			psels = <NRF_PSEL(UART_RX, 1, 1)>,
				<NRF_PSEL(UART_TX, 1, 2)>;
			low-power-enable;
		};
	};

	i2c0_default: i2c0_default {
		group1 {
			psels = <NRF_PSEL(TWIM_SDA, 0, 27)>,
				<NRF_PSEL(TWIM_SCL, 0, 26)>;
			bias-disable;	
		};
	};

	i2c0_sleep: i2c0_sleep {
		group1 {
			psels = <NRF_PSEL(TWIM_SDA, 0, 27)>,
				<NRF_PSEL(TWIM_SCL, 0, 26)>;
			bias-disable;	
			low-power-enable;
		};
	};

	i2c1_default: i2c1_default {
		group1 {
			psels = <NRF_PSEL(TWIM_SDA, 0, 25)>,
				<NRF_PSEL(TWIM_SCL, 0, 24)>;
			bias-disable;	
		};
	};

	i2c1_sleep: i2c1_sleep {
		group1 {
			psels = <NRF_PSEL(TWIM_SDA, 0, 25)>,
				<NRF_PSEL(TWIM_SCL, 0, 24)>;
			bias-disable;
			low-power-enable;
		};
	};

	pwm0_default: pwm0_default {
		group1 {
			psels = <NRF_PSEL(PWM_OUT0, 0, 13)>;
			nordic,invert;
		};
	};

	pwm0_sleep: pwm0_sleep {
		group1 {
			psels = <NRF_PSEL(PWM_OUT0, 0, 13)>;
			low-power-enable;
		};
	};

	spi0_default: spi0_default {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 27)>,
				<NRF_PSEL(SPIM_MOSI, 0, 26)>,
				<NRF_PSEL(SPIM_MISO, 0, 29)>;
		};
	};

	spi0_sleep: spi0_sleep {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 27)>,
				<NRF_PSEL(SPIM_MOSI, 0, 26)>,
				<NRF_PSEL(SPIM_MISO, 0, 29)>;
			low-power-enable;
		};
	};

	spi1_default: spi1_default {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 31)>,
				<NRF_PSEL(SPIM_MOSI, 0, 30)>,
				<NRF_PSEL(SPIM_MISO, 1, 8)>;
		};
	};

	spi1_sleep: spi1_sleep {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 31)>,
				<NRF_PSEL(SPIM_MOSI, 0, 30)>,
				<NRF_PSEL(SPIM_MISO, 1, 8)>;
			low-power-enable;
		};
	};

	spi2_default: spi2_default {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 19)>,
				<NRF_PSEL(SPIM_MOSI, 0, 20)>,
				<NRF_PSEL(SPIM_MISO, 0, 21)>;
		};
	};

	spi2_sleep: spi2_sleep {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 19)>,
				<NRF_PSEL(SPIM_MOSI, 0, 20)>,
				<NRF_PSEL(SPIM_MISO, 0, 21)>;
			low-power-enable;
		};
	};

	qspi_default: qspi_default {
		group1 {
			psels = <NRF_PSEL(QSPI_SCK, 0, 19)>,
				<NRF_PSEL(QSPI_IO0, 0, 20)>,
				<NRF_PSEL(QSPI_IO1, 0, 21)>,
				<NRF_PSEL(QSPI_IO2, 0, 22)>,
				<NRF_PSEL(QSPI_IO3, 0, 23)>,
				<NRF_PSEL(QSPI_CSN, 0, 17)>;
		};
	};

	qspi_sleep: qspi_sleep {
		group1 {
			psels = <NRF_PSEL(QSPI_SCK, 0, 19)>,
				<NRF_PSEL(QSPI_IO0, 0, 20)>,
				<NRF_PSEL(QSPI_IO1, 0, 21)>,
				<NRF_PSEL(QSPI_IO2, 0, 22)>,
				<NRF_PSEL(QSPI_IO3, 0, 23)>;
			low-power-enable;
		};
		group2 {
			psels = <NRF_PSEL(QSPI_CSN, 0, 17)>;
			low-power-enable;
			bias-pull-up;
		};
	};

	spi3_default: spi3_default {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 1, 15)>,
				<NRF_PSEL(SPIM_MISO, 1, 14)>,
				<NRF_PSEL(SPIM_MOSI, 1, 13)>;
		};
	};

	spi3_sleep: spi3_sleep {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 1, 15)>,
				<NRF_PSEL(SPIM_MISO, 1, 14)>,
				<NRF_PSEL(SPIM_MOSI, 1, 13)>;
			low-power-enable;
		};
	};

};

Strangely there is one more sensor on the same line and that sensor is working properly with this configuration. I have been using the same sensor and same hardware which was working on nrf5 SDK and recently ported the project to NCS 2.2.0.

Please help in resolving this

[Sigurd Hellesvik]

Hi,

You have 4 I2C devices connected to the nRF52840 right?

Do you see this error only if all are configured? Do you see the error for any one I2C device if you only try to use one in one app, and then another app with only one sensor and so on?

Regards,
Sigurd Hellesvik

[Gaurav]

Sigurd Hellesvik I have tested with stand alone too but there also it never worked.

But the other sensor (STC - fuel gauge) that works without fail.

[Sigurd Hellesvik]

I think I am missing some of the overview.

Can you list which sensors:

1. work all the time
2. work some of the time
3. never works

[Gaurav]

Other two sensor on the same i2c line (i2c0) works properly without fail. But only LSM6DSOX one fails.

I have disabled all the other communications which were using same pins of SDA and SCL (like SPI and UART) but still facing the same issue.

Marking again : All the sensors on the hardware works perfectly on nrf5 based SDK, having issues after porting thats why doubting configuration files.

[Gaurav]

Answering your query on this -

1. STC(fuel guage) address:0x70 and MLX(temp sensor) address : 0x3A, works all the time

2. Heart rate sensor (MAXM) address : 0x62 on i2c line 1 works sometimes, LSM only worked only one time so keeping it in 3 category

3. LSM6DSOX (0x6A) never worked.

[Sigurd Hellesvik]

Thanks for the overview, I think I understand the issue better now.

I suggest that we try to make LSM6DSOX work alone first, and then move on from there.

Set CONFIG_SENSOR_LOG_LEVEL_DBG and see if we get any useful information from that.

Also, if you want, try to debug the file zephyr\drivers\sensor\lsm6dso\lsm6dso.c, and see if you can see what happens there.

Do you have oscillosocope or logic analyzator traces from the I2C lines? Maybe that could give some hints.

[Gaurav]

Sure Sigurd Hellesvik I try once more with stand alone LSM.

But are you finding any fundamental issue with my DTS file with respect to the schematic shared?

[Sigurd Hellesvik]

Gaurav said:

But are you finding any fundamental issue with my DTS file with respect to the schematic shared?

From a look, it seems fine.
But in my experience, it is very hard to spot errors through staring at code

[Gaurav]

But see if my hardware already has pull up resistor, so I should be using bias-disabled on pin ctrl config..right?

any other flag that can be missing?

[Sigurd Hellesvik]

By the way, have you seen our I2C course?

Gaurav said:

But see if my hardware already has pull up resistor, so I should be using bias-disabled on pin ctrl config..right?

Our nRF52840DK pinctrl for i2c does not set any flags for i2c.

[Gaurav]

Hi Sigurd Hellesvik 

I have followed dev academy religiously in making this project including i2c.

See if only one sensor out of 4 sensor not working is the problem, on same config others are working and this is not that`s the problem.

I have disable rest of the communication to refrain from pin control conflicts -

&spi0 {
	status = "disabled";
};

&spi1 {
	status = "disabled";
};

&uart0 {
	status = "disabled";
};

&uart1 {
	status = "disabled";
};

But still nothing.